Messages in this thread |  | | Date | Mon, 6 Jan 2003 12:12:04 +0100 | From | Pavel Machek <> | Subject | Re: [ACPI] acpi_os_queue_for_execution() |
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Hi!
> > Acpi seems to create short-lived kernel threads, and I don't quite > > understand why. > > > > In thermal.c > > > > > > tz->timer.data = (unsigned long) tz; > > tz->timer.function = acpi_thermal_run; > > tz->timer.expires = jiffies + (HZ * > > sleep_time) / 1000; > > add_timer(&(tz->timer)); > > > > and acpi_thermal_run creates kernel therad that runs > > acpi_thermal_check. Why is not acpi_thermal_check called directly? I > > don't like idea of thread being created every time thermal zone needs > > to be polled... > > Are we allowed to block in a timer callback? One of the things > thermal_check does is call a control method, which in turn can be very > slow, sleep, etc., so I'd guess that's why the code tries to execute > things in its own thread.
But... Creating a kernel thread can block, too? [Correct me if I'm wrong, but creating a kernel thread looks like a *lot* of semaphores taken to me].
Pavel -- Casualities in World Trade Center: ~3k dead inside the building, cryptography in U.S.A. and free speech in Czech Republic. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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